Adjustable scaffold.



No. 722,498. P'ATENTED MAR. 10, 1903: 0. C. DONEGKER & J. A. NAGLE.

ADJUSTABLE SCAFPOLD.

APPLICATION FILED SEPT. 5. 1902.

H0 MODEL.

.IIMIJI 4 UNITED STATES PATENT OFFICE.

ORN DONECKER AND JACOB A. NAGLE, OF ALLENTOWN, PENN- SYLVANIA.

ADJUSTABLE SCAFFOLD.

SPECIFICATION forming` part of Letters Patent No. 722,498, dated March10, 1903.

Application filed September 5, 1902. Serial No. 122,254. (No model.)

T0 @ZZ whom t 11i/Cty concern.;

Be it known that we, ORIN C. DONECKER and JACOB A. NAGLE, citizens ofthe United States, residing at Allentown, Lehigh county, State ofPennsylvania, have invented a new and useful Improvement in AdjustableScaffolds, of which the following is a specification.

Our invention consists of a novel construction of adjustable scaoldswherein novel means are provided for raising the scaold and for lockingthe same in its adjusted position, means being provided for supportingthe locking-pawl in a very rigid and eective manner, so that thestructure is very strong and efficient under all conditions.

Figure l represents a side elevation, partially in section, of anadjustable scaffold embodying ourinvention. Fig. 2 represents a frontelevation of one of the standards seen in Fig. 1. Fig. 3 represents, onan enlarged scale, a perspective view showing the manner of bracing theupper portion of the uprights and securing the locking-pawl in position.Fig. 4 represents a section on linea: Fig. l. Fig. 5 represents a sideelevation of the elevating device seenin Fig. 1. Fig. 6 represents afront elevation of Fig. 5; Fig. 7 represents a side elevation of thelocking-pawl in adetached position. Fig. 8 represents a front elevationof Fig. 7.

Similar numerals of reference indicate corresponding parts in thefigures.

Referring to the drawings, 1 designates the base of the standards, fromwhich extend the substantially parallel uprights 2 and 3, said uprightsbeing braced by the irons 4.

5 represents a rack-bar which is located between the uprights 2 and 3and is provided with ratchet-teeth 6, which are engaged by the nose ofthe pawl 7, which is mounted on the pin 8, which latter projects througha tion, since it is adapted not only to reinforce the upper portion ofthe parallel uprights 2 and 3, but it also serves as a bearing for theends of the pin or rod 8,'which supports the pawl. It will be apparentto those skilled in the art that it is necessary that the supportingdevice, as the pawl 7, which sustains the weight of the bar 5 andscaffold 12, must be as rigidly supported as possible, and by locatingthe ends of the supporting-pin 8 in the metallic or other band 9 asdescribed a durable and efficient structure is produced, as is evident.

13 represents a band surrounding the upper portion of the uprights 2 and3, so that said uprights are held in a relatively fixed position.The-.bar 5 is raised by the application of the pawl 14 to theratchet-teeth 6, said pawl being pivotally mounted in the lever 15,whichis fulcrumed on the pin 1G, mounted in suitable bearings.

It will be apparent to those skilled in the art that in practice aplurality of standards or supporting devices, such as the uprights 2 and3, are employed and that the scaold or ooring 12 is supported at or nearits extremities or outer portions, so that all portions thereof arerigidly sustained. The rack 5 is raised by rocking the lever 15 onits'fulcrum, and it will be apparent that a downward movement of thescaffold 12 and said rack 5 will be prevented by the engagement of theend of the pawl 7 with the contiguous ratchetteeth. It will also beapparent that the pin S, which supports the pawl 7, is firmly secured inposition by means of the reliable engagement of its ends in the band 9,so that the latter serves not only to reinforce the upper` ends of theuprights 2 and 3, but it also serves to strengthen the upright 3 aroundthe groove 10 where it is weakest.

It will be apparent that various changes may be made by those skilled inthe art which may come within the scope of our invention, and we do not,therefore, desire to be limited to the exact construction herein shownand described.

Having thus described our invention, what we claim as new, and desire tosecure by Letters Patent, is-

1. In an adjustable scaold, a plurality of IOO uprights, a rack-barsupported between'said uprights, a slot in one of said uprights, a bandsurrounding said uprights in proximity to said slot, a spring-pressedpawl mounted in said slot, a pin supporting said pawl and extendingtransversely over said slot and hav-- is supported, each of saidrack-bars being held between uprights, a slot in one of said uprights, aband around said uprights and slot, a pawl mounted in said slot, a pinsupporting said bar and havingits ends located in said band, a leverpivotally mounted on one of said uprights and a pawl carried by saidlever and adapted to be moved in unison therewith for the purpose ofraising said rack-bar.

In testimony whereof we have signed our names to this specification inthe presence of two subscribing witnesses.

ORIN C. DONECKER. JACOB A. NAGLE.

Witnesses:

W. D. STERNER, B. A. LAUB.

